表油菜素内酯对月季切花保鲜作用的研究

本文初步探讨了表油菜素内酯（epiBR）对瓶插月季切花的保鲜作用。与对照（蒸馏水）和基本液（2％蔗糖＋500mgL-1柠檬酸＋250mgL-8-羟基喹啉＋25mgAgNO3）相比,经epiBR处理（基本液＋0．1mgL-1epiBR）的月季切花花枝坚挺,蓝变延迟,瓶插寿命延长1-1.5倍。测定有关生理指标表明,epiBR处理对月季切花瓶插花枝前期鲜重的增加及后期的保持有明显作用。并显著延缓花瓣和叶片质膜相对透性的增加,还能使瓶插前期花瓣还原糖含量增加。epiBR处理对花瓣蛋白质和叶片叶绿素含量变化无明显影响,而对花瓣花青素水平下降有轻微的促进作用。     

金花茶茶花的营养成分分析

该研究采用氨基酸自动分析仪、分光光度法等对金花茶花蕾、开放花和初谢花的营养成分进行了比较分析。结果表明:金花茶茶花中主要营养成分是碳水化合物,含有丰富的水溶性糖和粗纤维。茶花中的脂肪、粗纤维和水溶性糖含量随花蕾至开放的形成过程呈增加趋势,谢花后其含量呈下降趋势。开放花中总黄酮、皂甙、儿茶素、VE含量比花蕾和谢花中含量高。金花茶花蕾、开放花和初谢花三个阶段中氨基酸总量分别是7.44、5.14、5.00 g·100 g~(-1)。金花茶茶花含有丰富的氨基酸,花蕾内氨基酸含量尤为丰富。综合表明,金花茶茶花具较高的开发利用价值。该研究结果为了解金花茶花朵不同采收期的营养组成以及金花茶花朵的开发及采收利用提供了科学依据。     

广西野生花卉资源的研究

记述了广西野生花卉资源的概况 ,5个基本特点和 6个主要类群。同时也对产地的自然环境作了简介 ,并对广西野生花卉的保护和开发提出了建议。广西野生花卉的 5个主要特点是 :花卉种类的丰富性、种质资源的珍贵性、生长基质的特殊性、草本性状的显著性和资源分布的不均性。其 6个主要类群是 :山茶科、杜鹃科、兰科、木兰科、百合科和苦苣苔科。     

Mecardonia tenella (Plantaginaceae) Attracts Oil-, Perfume-, and Pollen-Gathering Bees in Southern Brazil

Floral characteristics often indicate the pollinators' functional group visiting the plant and the pollination syndromes associated with them. This idea has been challenged in the past decades due to increasing evidence that most plants, including those exhibiting floral syndromes, are visited by large arrays of species that differ in their effectiveness as pollinators. Our study focuses on Mecardonia tenella (Plantaginaceae) from the Araucaria forest of southern Brazil, which exhibits characteristics of the oil flower pollination syndrome. However, it is visited by three types of functional groups of bees: male orchid bees, oil-collecting bees, and pollen-seeking bees. The relative contribution of each functional group to the plant's reproductive success was estimated based on their pollen load, visitation frequency, and morphology. We assessed resources, phenology, and breeding system of M. tenella . Our results indicate that flowers lack nectar, but volatiles, lipids, and pollen are resources that can be gathered by visitors. This combination of floral traits and visitors' assemblage makes M. tenella a challenge to the concept of pollination syndromes. Our findings indicate that the current interactions may not reflect the circumstances under which some floral traits of this plant were selected.     

中国特有种——沙芥繁育系统和传粉生物学研究

运用定位观察、杂交指数、花粉-胚珠比、套袋试验和重力玻片法等方法,对沙芥自然居群和人工栽培种群的开花日动态、繁育系统和传粉习性进行了研究.结果显示:沙芥在自然居群和人工栽培种群开花日高峰分别在19:00和15:00～18:00.沙芥繁育系统为异花授粉植物.沙芥传粉媒介中风的飘移能力非常微弱;沙芥自然居群的访花昆虫有19种,分属于6个目;人工栽培种群的访花昆虫有11种,分属于6个目.意大利蜜蜂、熊蜂、黑带食蚜蝇和拟蜂食蚜蝇是两个居群共有的主要传粉昆虫,在自然居群熊蜂每天的访花频率呈双峰曲线,其中访花最高峰与开花日高峰基本重叠.     

野葛花醇提物中异黄酮含量及其抗氧化活性测定

以葛花苷为标准品,对野葛花醇提物的氯仿、乙酸乙酯、正丁醇萃取物及水溶物4部分中的异黄酮含量进行测定,并采用DPPH·法对各萃取物进行自由基清除实验.结果显示,(1)氯仿、乙酸乙酯、正丁醇萃取物及水溶物4部分的异黄酮含量分别为35.27%、53.42%、52.13%和2.34%.(2)抗氧化实验显示, 4 部分清除DPPH·的IC50值分别为252、49、197和344 μg/mL.(3)相关性分析表明,野葛花醇提物各萃取部分的抗氧化活性主要来自于其中含有的异黄酮类化合物.研究表明野葛花醇提物的乙酸乙酯和正丁醇萃取部分异黄酮含量较高;氯仿、乙酸乙酯、正丁醇萃取物及水溶物4部分对DPPH自由基均有一定的清除作用,其中以乙酸乙酯萃取物的效果最佳;表明异黄酮是一种天然的抗氧化剂,具有较强的抗氧化作用.     

The structure and roles of sterile flowers in Viburnum macrocephalum f. keteleeri (Adoxaceae)

The formation and ecological roles of sterile flowers in flowering plants are interesting issues in floral biology and evolution. Here, we investigated the morphological and anatomical characteristics of both fertile and sterile flowers of Viburnum macrocephalum f. keteleeri, a self-incompatible and insect-pollinated shrub, during different developmental stages of flowers. In addition, pollinator visitation rates and fruit set were determined in intact inflorescences and those with sterile flowers removed. The results indicate that sterile and fertile flowers were developmentally similar during early developmental stages, and that development of the flower types diverged about 15 days before flowering. In addition, pollinator visitation rates, number of pollen grains on stigmas and fruit set were significantly higher in inflorescences with sterile flowers than those without sterile flowers. The results suggest that sterile flowers of this species evolved from fertile flowers under long-term selective pressure, and play a crucial role in enhancing reproductive success through effectively attracting pollinators to the plant and thus enhancing fruit set.